MythBusters: Is Peyton Manning's regression bound to continue in '15?

In our "MythBusters" series, SI.com's Doug Farrar uses tape, statistics and conversations with some of the NFL's most knowledgeable voices to debunk storylines that have inexplicably gained traction. This installment is a very deep dive into Peyton Manning's 2014 season, asking whether the rumors of his future demise are overstated.

Last December, Peyton Manning threw just three touchdowns and six interceptions. The 38-year-old followed that up with a postseason performance in which he averaged fewer than five yards per attempt and completed fewer than 57% of his passes (including one completion in eight attempts on passes 20 yards or more). That kind of play, coupled with a quadriceps injury that impacted his accuracy and velocity, is going to create legitimate reason for concern about his future in the NFL—even for Manning.

2014 was still a relatively great season for Manning—he completed 395 passes in 597 attempts for 4,727 yards, 39 touchdowns and 15 interceptions in the regular season, and finished third in Football Outsiders' opponent-adjusted efficiency ratings for quarterbacks. Still, that rough December had people wondering whether it was time for Manning to consider his future, including Manning himself. After the Broncos lost 24-13 in the divisional round to the Colts, the future first-ballot Hall-of-Famer walked away to consider his options. The decision to return wasn't immediate.

In the end, of course, Manning decided to give it one more shot. The question is, will he be the quarterback he once was, or is he going to have to deal with the physical and schematic decline inevitable to even the greatest athletes?

While Manning was making his decision, the Broncos were making changes of their own. Coach John Fox was replaced by former Denver quarterback and Texans coach Gary Kubiak. Offensive coordinator Adam Gase took the same position in Chicago (under Fox, who was hired as the head coach there) after an abortive attempt to navigate the 49ers' front office as a head coaching candidate. TE Julius Thomas, who led the Broncos in touchdown receptions with 12 in 2014, was lured to Jacksonville by a lucrative free-agent contract. Left tackle Ryan Clady was lost for the 2015 season to a torn ACL suffered in a May practice.

And Manning, whose 2012 contract (five years, $96 million) was essentially a series of one-year deals dependent on annual physicals, was asked by the organization to take a $10 million pay cut this offseason. In the end, player and team agreed to a $4 million reduction from $19 million to $15 million, and it's reasonable to say that if Manning was still the Manning of old, this would never have happened. It also speaks to the team's need to reinforce talent at other positions, and perhaps an awareness that the time to think about life without Manning is now.

That's a smart front-office strategy. We don't know how much Manning has left in the tank—and how adroitly his new coaching staff can extract it.

The Scheme

When Gase became Denver's offensive coordinator in 2013, he added a number of schematic constructs to a Broncos offense that was already more varied than anything Manning ever ran in Indianapolis. With the Colts in the first decade of the new millennium, Manning presided over an offense that generally ran more three-wide, single-back formations than any other team. Though the routes were complex from the snap, especially when TE Dallas Clark became a weapon in the flex position—Manning didn't really have the advantages given to those quarterbacks who benefitted from what my friend Greg Cosell of NFL Films likes to call "receiver distribution and location."

Under Gase, the Broncos would use trips and bunch formations, switch releases with unconventional receivers, backs in motion to set defensive fronts on edge, and easy first-read receiver sets to accelerate the success of a quick passing game. Manning ran it to perfection for the most part, and enjoyed the most prolific season of his career in 2013—450 completions in 659 attempts for 5,477 yards and 55 touchdowns. Until he met the Seahawks in Super Bowl XLVIII, there wasn't a defense that Manning couldn't disassemble, and things started well in 2014.

In September of last season, he completed 74 passes in 111 attempts for 814 yards, eight touchdowns and one interception. In October, he was right on course with 100 completions in 141 attempts for 1,320 yards, 14 touchdowns and two interceptions. November saw a bit of a regression with 144 completions in 224 attempts for 1,603 yards, 14 touchdowns and six interceptions, though one could argue that the reduction in efficiency was a function of passing volume. Then, Manning's nightmare December and January, and here we are, discussing his future in Kubiak's offense.

Kubiak has already said that he wants Manning under center more often, because it fits into his ideal offense—a power zone-blocking system in which run-action (in which linemen fire out on passes as if they're run-blocking) and boot action (in which quarterbacks roll out after play-action) are primary aspects. It's not likely that Manning will be rolling right on 300 of his 500 passing attempts, so the coach will have to adapt there. Manning ran the stretch and slice play-action plays to perfection in Indianapolis; the entire offense would roll to the right after the snap, and the playfake to the back would stress the defense to the breaking point. So, there may be a return to a moveable pocket as opposed to a mobile quarterback.

Kubiak also intends to use the Pistol formation as the Broncos did in 2014, which is a smart play. It allows Manning the shotgun advantage, and still gives the deception element crucial to play-action.

“In my conversations with him, he was not under center much because he wasn’t feeling real good," Kubiak said of Manning at the league meetings in March. "When I’ve watched him play under center, the steps and all those things, he’s been doing it for years. I don’t think that’s a big adjustment. Now, how much you do it probably depends on how comfortable he is and how successful we are with it. One of the things about being under center is your back is not offset, so there is obviously tendencies in football to what you do and then how you line up. The Pistol has created a good situation because even though you’re in the gun, the back is still directly behind the quarterback and you have a two-way go.”

So, it sounds like a reasonable compromise there. However, the primary cause for concern when superimposing Manning into Kubiak's offense is how Kubiak's offense looked before the Texans fired him on December 6, 2013. QB Matt Schaub had completely fallen apart after a series of pick-sixes, and opponents were so onto Kubiak's ideas, they were perfecting responses to them in practice.

With 2:49 left in the first half of Houston's Week 3 30–9 loss to the Ravens, Schaub threw a pick-six to linebacker Daryl Smith, which Smith saw coming. The Texans ran bunch left out of the Pistol, and they had two tight ends—Owen Daniels and Garrett Graham—in the formation. They tried to lift Smith out of his spot with Graham running straight up the seam, and that would have worked except for one fact: The Ravens knew that in such a route combo, Schaub liked to work back to Daniels with the angle route underneath.

"It was just something we've seen on film through the week," Smith said after the game. "We've been getting pressure on him, but he was getting rid of the ball pretty quick. I knew I had a chance to jump it. We got pressure on that play, and I jumped the route, and I was able to take it for a touchdown."

Indeed. One week later, the Texans lost an overtime heartbreaker to the Seahawks, and the play that sent the game into extra time was Richard Sherman's 58-yard interception return touchdown with 2:51 left in regulation. Houston started the play with Andre Johnson in the right slot and Daniels outside the numbers. At the moment Daniels motioned inside to stack, Sherman motioned for safety Kam Chancellor to head up to the line to blitz. Reading this route concept correctly meant that the Seahawks knew there wouldn't be anyone to block Chancellor, and he'd get a free release off the line. That's what happened, and when Schaub ran boot-action to his right and turned around to make the throw, Chancellor was already in his face.

The problem wasn't Schaub's bad throw—bad throws happen, especially under surprise pressure. The problem was that the Seahawks absolutely knew what was up based on situation and personnel.

"I wasn't watching it per se—I knew it was coming," Sherman said. "We ran the same play against our scout team on Friday. It's a play we'd seen on film that they like to run in short-yardage situations—roll Schaub out, and send the receiver on an 'in-and-back-out' route with a corner route behind it. You jump to the guy in the flat. ... As soon as they made the call, and we knew the situation they were in—it was third-and-short, and it was that play they liked."

Now, you can say that defenses generally know what offenses are doing, and that's true. But the extent to which Kubiak's strategies were intercepted by his opponents should raise a few eyebrows. Common perception is that with all his experience, Manning will still run the show on the field. Quite possible, but Manning had a great partner in Gase. This new relationship may not work out as well.

The Stats

Perhaps we can get a bit more insight as to Kubiak's intentions by looking at the 2014 Ravens, when Kubiak was their offensive coordinator. In that offense, Joe Flacco put up his highest completion percentage since 2010 (62.1) and turned his touchdown/interception ratio around from 19/22 to 27/12. Kubiak's blocking scheme also allowed Justin Forsett to have a career year, which is good news for Denver's cadre of running backs.

Baltimore's percentage of shotgun plays completely plummeted under Kubiak, from 73.1% in 2013 to a league-low 24.1%. However, according to Football Outsiders' metrics, only the Cowboys were more effective out of shotgun than the Ravens. That could be a function of small sample size to a point, but it's worth considering, because the Broncos ran shotgun 73% of the time, fifth-most in the league, and they were the fourth-most effective team in either shotgun or pistol. Denver gained 6.6 yards per shotgun play, and 5.4 yards per play when Manning was under center. And while that's partially a function of a higher rate of passing plays out of shotgun, the Broncos ran a ton out of the Pistol, as well—as Kubiak inferred, Pistol is an ideal run formation with a zone-blocking line.

Flacco ceded to Kubiak's love of play-action to a point, but not as much as you might think. In 2013, he ran play-action on 13-3% of his dropbacks, completing 56 of 81 passes for 630 yards, six touchdowns and three interceptions. In 2014 under Kubiak, Flacco's play-action rate increased to 18.5, with 66 completions in 102 attempts for 792 yards, and the same number of touchdowns and interceptions. Flacco's efficiency was a bit higher in play-action, but nothing really remarkable.

And that's not the case with Manning, who, according to Pro Football Focus' metrics, was comparatively ghastly when using play-action in 2014. He did so on 22.5% of his dropbacks, completing 86 of 132 passes for 1,354 yards, five touchdowns and eight of his 15 interceptions. Not good at all, though it should be said that he was much better using play-action in his historic 2013 season, with 18 touchdowns and three picks on 25.6% of his total dropbacks.

The Player

But here, we're discussing the gap between 2013 and '14, and what it tells us about Manning's '15 and beyond. Manning reportedly tore his right quadriceps muscle on Dec. 14 against the Chargers, but he'd already had a no-touchdown, two-pick game against the Bills the week before, and there was a rough mid-season stretch against the Patriots and Rams, when he totaled three touchdowns and four picks in those two games. He did have a five-touchdown performance against the Raiders in between, but he also threw two picks.

Of greater concern was the game after the injury—a 37–28 loss to the Bengals on December 22, when he threw four interceptions, the most he'd given up as a Bronco. Not all the interceptions were his fault, but tape review of that game brought up some real concerns.

This pick came with 2:50 left in the game. Manning runs a quick play-action to C.J. Anderson, and hurries a throw to Demaryius​ Thomas that's picked off by cornerback Dre Kirkpatrick for a 30-yard touchdown. Manning is falling away from the throw, his feet aren't set, the read is weird and he misses Kirkpatrick's inside position ... the perfect storm.

Manning threw another pick to end the next drive—again to Thomas, and again picked off by Kirkpatrick. This looks like an aborted switch concept downfield, but the alarming asapect is the lack of velocity Manning's able to put on the throw despite the fact that he plants his foot.

Against the Colts in the divisional round, Manning kept throwing deep balls despite the fact that he was air-mailing just about everything—again, he completed one pass in eight that he threw over 20 yards on the day. This one to Thomas came with 2:55 left in the first half. Manning isn't quite on his base, and he simply doesn't have the arm strength to counter mechanical issues with consistent pinpoint velocity from upper-body throws.

On the next play, he overthrew Emmanuel Sanders to the right side—again, from a less-than-solid base, and with highly questionable accuracy.

Some will tell you that as soon as Manning is healthy, his velocity issues will be solved. I'd like to believe that, but I'm a bit more reserved about the idea. There was a definite regression in pure zip in his throws in 2014, pre-and post-injury. In a system set up to maximize his remaining and obvious gifts, that wouldn't be a huge problem. A lot of quarterbacks get by without a Howitzer for an arm, and Manning's arm strength has never been his primary asset. He's a hyper-intelligent player who throws with anticipation and reads defense at a professorial level. That said, if he can't get the ball where it needs to go in a system that defenses find easier to read... well, that's a problem.

Is Manning's regression inevitable in 2015? Not entirely, but the more you look at the complete picture, it seems far more likely than not.

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